/*      $NetBSD: isakmp_base.c,v 1.14 2025/03/07 15:55:29 christos Exp $        */

/*      $KAME: isakmp_base.c,v 1.49 2003/11/13 02:30:20 sakane Exp $    */

/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/* Base Exchange (Base Mode) */

#include "config.h"

#include <sys/types.h>
#include <sys/param.h>

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#if TIME_WITH_SYS_TIME
# include <sys/time.h>
# include <time.h>
#else
# if HAVE_SYS_TIME_H
#  include <sys/time.h>
# else
#  include <time.h>
# endif
#endif

#include "var.h"
#include "misc.h"
#include "vmbuf.h"
#include "plog.h"
#include "sockmisc.h"
#include "schedule.h"
#include "debug.h"

#ifdef ENABLE_HYBRID
#include <resolv.h>
#endif

#include "localconf.h"
#include "remoteconf.h"
#include "isakmp_var.h"
#include "isakmp.h"
#include "evt.h"
#include "oakley.h"
#include "handler.h"
#include "ipsec_doi.h"
#include "crypto_openssl.h"
#include "pfkey.h"
#include "isakmp_base.h"
#include "isakmp_inf.h"
#include "vendorid.h"
#ifdef ENABLE_NATT
#include "nattraversal.h"
#endif
#ifdef ENABLE_FRAG
#include "isakmp_frag.h"
#endif
#ifdef ENABLE_HYBRID
#include "isakmp_xauth.h"
#include "isakmp_cfg.h"
#endif

/* %%%
 * begin Identity Protection Mode as initiator.
 */
/*
 * send to responder
 *      psk: HDR, SA, Idii, Ni_b
 *      sig: HDR, SA, Idii, Ni_b
 *      rsa: HDR, SA, [HASH(1),] <IDii_b>Pubkey_r, <Ni_b>Pubkey_r
 *      rev: HDR, SA, [HASH(1),] <Ni_b>Pubkey_r, <IDii_b>Ke_i
 */
int
base_i1send(struct ph1handle *iph1, vchar_t *msg) /* must be null */
{
        struct payload_list *plist = NULL;
        int error = -1;
#ifdef ENABLE_NATT
        vchar_t *vid_natt[MAX_NATT_VID_COUNT] = { NULL };
        int i, vid_natt_i = 0;
#endif
#ifdef ENABLE_FRAG
        vchar_t *vid_frag = NULL;
#endif
#ifdef ENABLE_HYBRID
        vchar_t *vid_xauth = NULL;
        vchar_t *vid_unity = NULL;
#endif
#ifdef ENABLE_DPD
        vchar_t *vid_dpd = NULL;
#endif


        /* validity check */
        if (msg != NULL) {
                plog(LLV_ERROR, LOCATION, NULL,
                        "msg has to be NULL in this function.\n");
                goto end;
        }
        if (iph1->status != PHASE1ST_START) {
                plog(LLV_ERROR, LOCATION, NULL,
                        "status mismatched %d.\n", iph1->status);
                goto end;
        }

        /* create isakmp index */
        memset(&iph1->index, 0, sizeof(iph1->index));
        isakmp_newcookie((caddr_t)&iph1->index, iph1->remote, iph1->local);

        /* make ID payload into isakmp status */
        if (ipsecdoi_setid1(iph1) < 0)
                goto end;

        /* create SA payload for my proposal */
        iph1->sa = ipsecdoi_setph1proposal(iph1->rmconf,
                                           iph1->rmconf->proposal);
        if (iph1->sa == NULL)
                goto end;

        /* generate NONCE value */
        iph1->nonce = eay_set_random(iph1->rmconf->nonce_size);
        if (iph1->nonce == NULL)
                goto end;

#ifdef ENABLE_HYBRID
        /* Do we need Xauth VID? */
        switch (iph1->rmconf->proposal->authmethod) {
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_PSKEY_I:
        case OAKLEY_ATTR_AUTH_METHOD_HYBRID_RSA_I:
        case OAKLEY_ATTR_AUTH_METHOD_HYBRID_DSS_I:
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_RSASIG_I:
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_DSSSIG_I:
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_RSAENC_I:
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_RSAREV_I:
                if ((vid_xauth = set_vendorid(VENDORID_XAUTH)) == NULL)
                        plog(LLV_ERROR, LOCATION, NULL,
                             "Xauth vendor ID generation failed\n");

                if ((vid_unity = set_vendorid(VENDORID_UNITY)) == NULL)
                        plog(LLV_ERROR, LOCATION, NULL,
                             "Unity vendor ID generation failed\n");
                break;
        default:
                break;
        }
#endif
#ifdef ENABLE_FRAG
        if (iph1->rmconf->ike_frag) {
                vid_frag = set_vendorid(VENDORID_FRAG);
                if (vid_frag != NULL)
                        vid_frag = isakmp_frag_addcap(vid_frag, 
                            VENDORID_FRAG_BASE);
                if (vid_frag == NULL)
                        plog(LLV_ERROR, LOCATION, NULL, 
                            "Frag vendorID construction failed\n");
        }
#endif
#ifdef ENABLE_NATT
        /* Is NAT-T support allowed in the config file? */
        if (iph1->rmconf->nat_traversal) {
                /* Advertise NAT-T capability */
                memset (vid_natt, 0, sizeof (vid_natt));
#ifdef VENDORID_NATT_00
                if ((vid_natt[vid_natt_i] = set_vendorid(VENDORID_NATT_00)) != NULL)
                        vid_natt_i++;
#endif
#ifdef VENDORID_NATT_02
                if ((vid_natt[vid_natt_i] = set_vendorid(VENDORID_NATT_02)) != NULL)
                        vid_natt_i++;
#endif
#ifdef VENDORID_NATT_02_N
                if ((vid_natt[vid_natt_i] = set_vendorid(VENDORID_NATT_02_N)) != NULL)
                        vid_natt_i++;
#endif
#ifdef VENDORID_NATT_RFC
                if ((vid_natt[vid_natt_i] = set_vendorid(VENDORID_NATT_RFC)) != NULL)
                        vid_natt_i++;
#endif
        }
#endif

        /* set SA payload to propose */
        plist = isakmp_plist_append(plist, iph1->sa, ISAKMP_NPTYPE_SA);

        /* create isakmp ID payload */
        plist = isakmp_plist_append(plist, iph1->id, ISAKMP_NPTYPE_ID);

        /* create isakmp NONCE payload */
        plist = isakmp_plist_append(plist, iph1->nonce, ISAKMP_NPTYPE_NONCE);

#ifdef ENABLE_FRAG
        if (vid_frag)
                plist = isakmp_plist_append(plist, vid_frag, ISAKMP_NPTYPE_VID);
#endif
#ifdef ENABLE_HYBRID
        if (vid_xauth)
                plist = isakmp_plist_append(plist, 
                    vid_xauth, ISAKMP_NPTYPE_VID);
        if (vid_unity)
                plist = isakmp_plist_append(plist, 
                    vid_unity, ISAKMP_NPTYPE_VID);
#endif
#ifdef ENABLE_DPD
        if (iph1->rmconf->dpd) {
                vid_dpd = set_vendorid(VENDORID_DPD);
                if (vid_dpd != NULL)
                        plist = isakmp_plist_append(plist, vid_dpd, ISAKMP_NPTYPE_VID); 
        }
#endif  
#ifdef ENABLE_NATT
        /* set VID payload for NAT-T */
        for (i = 0; i < vid_natt_i; i++)
                plist = isakmp_plist_append(plist, vid_natt[i], ISAKMP_NPTYPE_VID);
#endif
        iph1->sendbuf = isakmp_plist_set_all (&plist, iph1);


#ifdef HAVE_PRINT_ISAKMP_C
        isakmp_printpacket(iph1->sendbuf, iph1->local, iph1->remote, 0);
#endif

        /* send the packet, add to the schedule to resend */
        if (isakmp_ph1send(iph1) == -1)
                goto end;

        iph1->status = PHASE1ST_MSG1SENT;

        error = 0;

end:
#ifdef ENABLE_FRAG
        if (vid_frag)
                vfree(vid_frag);
#endif 
#ifdef ENABLE_NATT
        for (i = 0; i < vid_natt_i; i++)
                vfree(vid_natt[i]);
#endif
#ifdef ENABLE_HYBRID    
        if (vid_xauth != NULL)
                vfree(vid_xauth);
        if (vid_unity != NULL) 
                vfree(vid_unity);
#endif 
#ifdef ENABLE_DPD
        if (vid_dpd != NULL)    
                vfree(vid_dpd);
#endif     

        return error;
}

/*
 * receive from responder
 *      psk: HDR, SA, Idir, Nr_b
 *      sig: HDR, SA, Idir, Nr_b, [ CR ]
 *      rsa: HDR, SA, <IDir_b>PubKey_i, <Nr_b>PubKey_i
 *      rev: HDR, SA, <Nr_b>PubKey_i, <IDir_b>Ke_r
 */
int
base_i2recv(struct ph1handle *iph1, vchar_t *msg)
{
        vchar_t *pbuf = NULL;
        struct isakmp_parse_t *pa;
        vchar_t *satmp = NULL;
        int error = -1;

        /* validity check */
        if (iph1->status != PHASE1ST_MSG1SENT) {
                plog(LLV_ERROR, LOCATION, NULL,
                        "status mismatched %d.\n", iph1->status);
                goto end;
        }

        /* validate the type of next payload */
        pbuf = isakmp_parse(msg);
        if (pbuf == NULL)
                goto end;
        pa = (struct isakmp_parse_t *)pbuf->v;

        /* SA payload is fixed postion */
        if (pa->type != ISAKMP_NPTYPE_SA) {
                plog(LLV_ERROR, LOCATION, iph1->remote,
                        "received invalid next payload type %d, "
                        "expecting %d.\n",
                        pa->type, ISAKMP_NPTYPE_SA);
                goto end;
        }
        if (isakmp_p2ph(&satmp, pa->ptr) < 0)
                goto end;
        pa++;

        for (/*nothing*/;
             pa->type != ISAKMP_NPTYPE_NONE;
             pa++) {

                switch (pa->type) {
                case ISAKMP_NPTYPE_NONCE:
                        if (isakmp_p2ph(&iph1->nonce_p, pa->ptr) < 0)
                                goto end;
                        break;
                case ISAKMP_NPTYPE_ID:
                        if (isakmp_p2ph(&iph1->id_p, pa->ptr) < 0)
                                goto end;
                        break;
                case ISAKMP_NPTYPE_VID:
                        handle_vendorid(iph1, pa->ptr);
                        break;
                default:
                        /* don't send information, see ident_r1recv() */
                        plog(LLV_ERROR, LOCATION, iph1->remote,
                                "ignore the packet, "
                                "received unexpecting payload type %d.\n",
                                pa->type);
                        goto end;
                }
        }

        if (iph1->nonce_p == NULL || iph1->id_p == NULL) {
                plog(LLV_ERROR, LOCATION, iph1->remote,
                        "few isakmp message received.\n");
                goto end;
        }

        /* verify identifier */
        if (ipsecdoi_checkid1(iph1) != 0) {
                plog(LLV_ERROR, LOCATION, iph1->remote,
                        "invalid ID payload.\n");
                goto end;
        }

#ifdef ENABLE_NATT
        if (NATT_AVAILABLE(iph1))
                plog(LLV_INFO, LOCATION, iph1->remote,
                     "Selected NAT-T version: %s\n",
                     vid_string_by_id(iph1->natt_options->version));
#endif

        /* check SA payload and set approval SA for use */
        if (ipsecdoi_checkph1proposal(satmp, iph1) < 0) {
                plog(LLV_ERROR, LOCATION, iph1->remote,
                        "failed to get valid proposal.\n");
                /* XXX send information */
                goto end;
        }
        VPTRINIT(iph1->sa_ret);

        iph1->status = PHASE1ST_MSG2RECEIVED;

        error = 0;

end:
        if (pbuf)
                vfree(pbuf);
        if (satmp)
                vfree(satmp);

        if (error) {
                VPTRINIT(iph1->nonce_p);
                VPTRINIT(iph1->id_p);
        }

        return error;
}

/*
 * send to responder
 *      psk: HDR, KE, HASH_I
 *      sig: HDR, KE, [ CR, ] [CERT,] SIG_I
 *      rsa: HDR, KE, HASH_I
 *      rev: HDR, <KE>Ke_i, HASH_I
 */
int
base_i2send(struct ph1handle *iph1, vchar_t *msg)
{
        struct payload_list *plist = NULL;
        vchar_t *vid = NULL;
        int need_cert = 0;
        int error = -1;

        /* validity check */
        if (iph1->status != PHASE1ST_MSG2RECEIVED) {
                plog(LLV_ERROR, LOCATION, NULL,
                        "status mismatched %d.\n", iph1->status);
                goto end;
        }

        /* fix isakmp index */
        memcpy(&iph1->index.r_ck, &((struct isakmp *)msg->v)->r_ck,
                sizeof(cookie_t));

        /* generate DH public value */
        if (oakley_dh_generate(iph1->approval->dhgrp,
                                &iph1->dhpub, &iph1->dhpriv) < 0)
                goto end;

        /* generate SKEYID to compute hash if not signature mode */
        switch (iph1->approval->authmethod) {
        case OAKLEY_ATTR_AUTH_METHOD_RSASIG:
        case OAKLEY_ATTR_AUTH_METHOD_DSSSIG:
#ifdef ENABLE_HYBRID
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_PSKEY_I:
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_RSASIG_I:
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_DSSSIG_I:
        case OAKLEY_ATTR_AUTH_METHOD_HYBRID_RSA_I:
        case OAKLEY_ATTR_AUTH_METHOD_HYBRID_DSS_I:
#endif
                break;
        default:
                if (oakley_skeyid(iph1) < 0)
                        goto end;
                break;
        }

        /* generate HASH to send */
        plog(LLV_DEBUG, LOCATION, NULL, "generate HASH_I\n");
        iph1->hash = oakley_ph1hash_base_i(iph1, GENERATE);
        if (iph1->hash == NULL)
                goto end;
        switch (iph1->approval->authmethod) {
        case OAKLEY_ATTR_AUTH_METHOD_PSKEY:
#ifdef ENABLE_HYBRID
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_PSKEY_I:
        case OAKLEY_ATTR_AUTH_METHOD_HYBRID_RSA_I:
        case OAKLEY_ATTR_AUTH_METHOD_HYBRID_DSS_I:
#endif
                vid = set_vendorid(iph1->approval->vendorid);

                /* create isakmp KE payload */
                plist = isakmp_plist_append(plist, iph1->dhpub, ISAKMP_NPTYPE_KE);

                /* create isakmp HASH payload */
                plist = isakmp_plist_append(plist, iph1->hash, ISAKMP_NPTYPE_HASH);

                /* append vendor id, if needed */
                if (vid)
                        plist = isakmp_plist_append(plist, vid, ISAKMP_NPTYPE_VID);
                break;
        case OAKLEY_ATTR_AUTH_METHOD_DSSSIG:
        case OAKLEY_ATTR_AUTH_METHOD_RSASIG:
#ifdef ENABLE_HYBRID
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_RSASIG_I:
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_DSSSIG_I:
#endif
                /* XXX if there is CR or not ? */

                if (oakley_getmycert(iph1) < 0)
                        goto end;

                if (oakley_getsign(iph1) < 0)
                        goto end;

                if (iph1->cert && iph1->rmconf->send_cert)
                        need_cert = 1;

                /* create isakmp KE payload */
                plist = isakmp_plist_append(plist, iph1->dhpub,
                                            ISAKMP_NPTYPE_KE);

                /* add CERT payload if there */
                if (need_cert)
                        plist = isakmp_plist_append(plist,  iph1->cert,
                                                    ISAKMP_NPTYPE_CERT);

                /* add SIG payload */
                plist = isakmp_plist_append(plist,
                    iph1->sig, ISAKMP_NPTYPE_SIG);

                break;
#ifdef HAVE_GSSAPI
        case OAKLEY_ATTR_AUTH_METHOD_GSSAPI_KRB:
                /* ... */
                break;
#endif
        case OAKLEY_ATTR_AUTH_METHOD_RSAENC:
        case OAKLEY_ATTR_AUTH_METHOD_RSAREV:
#ifdef ENABLE_HYBRID
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_RSAENC_I:
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_RSAREV_I:
#endif
                break;
        }

#ifdef ENABLE_NATT
        /* generate NAT-D payloads */
        if (NATT_AVAILABLE(iph1))
        {
                vchar_t *natd[2] = { NULL, NULL };

                plog (LLV_INFO, LOCATION, NULL, "Adding remote and local NAT-D payloads.\n");
                if ((natd[0] = natt_hash_addr (iph1, iph1->remote)) == NULL) {
                        plog(LLV_ERROR, LOCATION, NULL,
                                "NAT-D hashing failed for %s\n", saddr2str(iph1->remote));
                        goto end;
                }

                if ((natd[1] = natt_hash_addr (iph1, iph1->local)) == NULL) {
                        plog(LLV_ERROR, LOCATION, NULL,
                                "NAT-D hashing failed for %s\n", saddr2str(iph1->local));
                        goto end;
                }

                plist = isakmp_plist_append(plist, natd[0], iph1->natt_options->payload_nat_d);
                plist = isakmp_plist_append(plist, natd[1], iph1->natt_options->payload_nat_d);
        }
#endif

        iph1->sendbuf = isakmp_plist_set_all (&plist, iph1);

#ifdef HAVE_PRINT_ISAKMP_C
        isakmp_printpacket(iph1->sendbuf, iph1->local, iph1->remote, 0);
#endif

        /* send the packet, add to the schedule to resend */
        if (isakmp_ph1send(iph1) == -1)
                goto end;

        /* the sending message is added to the received-list. */
        if (add_recvdpkt(iph1->remote, iph1->local, iph1->sendbuf, msg) == -1) {
                plog(LLV_ERROR , LOCATION, NULL,
                        "failed to add a response packet to the tree.\n");
                goto end;
        }

        iph1->status = PHASE1ST_MSG2SENT;

        error = 0;

end:
        if (vid)
                vfree(vid);
        return error;
}

/*
 * receive from responder
 *      psk: HDR, KE, HASH_R
 *      sig: HDR, KE, [CERT,] SIG_R
 *      rsa: HDR, KE, HASH_R
 *      rev: HDR, <KE>_Ke_r, HASH_R
 */
int
base_i3recv(struct ph1handle *iph1, vchar_t *msg)
{
        vchar_t *pbuf = NULL;
        struct isakmp_parse_t *pa;
        int error = -1, ptype;
#ifdef ENABLE_NATT
        vchar_t *natd_received;
        int natd_seq = 0, natd_verified;
#endif

        /* validity check */
        if (iph1->status != PHASE1ST_MSG2SENT) {
                plog(LLV_ERROR, LOCATION, NULL,
                        "status mismatched %d.\n", iph1->status);
                goto end;
        }

        /* validate the type of next payload */
        pbuf = isakmp_parse(msg);
        if (pbuf == NULL)
                goto end;

        for (pa = (struct isakmp_parse_t *)pbuf->v;
             pa->type != ISAKMP_NPTYPE_NONE;
             pa++) {

                switch (pa->type) {
                case ISAKMP_NPTYPE_KE:
                        if (isakmp_p2ph(&iph1->dhpub_p, pa->ptr) < 0)
                                goto end;
                        break;
                case ISAKMP_NPTYPE_HASH:
                        iph1->pl_hash = (struct isakmp_pl_hash *)pa->ptr;
                        break;
                case ISAKMP_NPTYPE_CERT:
                        if (oakley_savecert(iph1, pa->ptr) < 0)
                                goto end;
                        break;
                case ISAKMP_NPTYPE_SIG:
                        if (isakmp_p2ph(&iph1->sig_p, pa->ptr) < 0)
                                goto end;
                        break;
                case ISAKMP_NPTYPE_VID:
                        handle_vendorid(iph1, pa->ptr);
                        break;

#ifdef ENABLE_NATT
                case ISAKMP_NPTYPE_NATD_DRAFT:
                case ISAKMP_NPTYPE_NATD_RFC:
                        if (NATT_AVAILABLE(iph1) && iph1->natt_options &&
                            pa->type == iph1->natt_options->payload_nat_d) {
                                natd_received = NULL;
                                if (isakmp_p2ph (&natd_received, pa->ptr) < 0)
                                        goto end;
                        
                                /* set both bits first so that we can clear them
                                   upon verifying hashes */
                                if (natd_seq == 0)
                                        iph1->natt_flags |= NAT_DETECTED;
                        
                                /* this function will clear appropriate bits bits 
                                   from iph1->natt_flags */
                                natd_verified = natt_compare_addr_hash (iph1,
                                        natd_received, natd_seq++);
                        
                                plog (LLV_INFO, LOCATION, NULL, "NAT-D payload #%d %s\n",
                                        natd_seq - 1,
                                        natd_verified ? "verified" : "doesn't match");
                        
                                vfree (natd_received);
                                break;
                        }
                        /* passthrough to default... */
#endif
                        /*FALLTHROUGH*/
                default:
                        /* don't send information, see ident_r1recv() */
                        plog(LLV_ERROR, LOCATION, iph1->remote,
                                "ignore the packet, "
                                "received unexpecting payload type %d.\n",
                                pa->type);
                        goto end;
                }
        }

#ifdef ENABLE_NATT
        if (NATT_AVAILABLE(iph1)) {
                plog (LLV_INFO, LOCATION, NULL, "NAT %s %s%s\n",
                      iph1->natt_flags & NAT_DETECTED ? 
                                "detected:" : "not detected",
                      iph1->natt_flags & NAT_DETECTED_ME ? "ME " : "",
                      iph1->natt_flags & NAT_DETECTED_PEER ? "PEER" : "");
                if (iph1->natt_flags & NAT_DETECTED)
                        natt_float_ports (iph1);
        }
#endif

        /* payload existency check */
        /* validate authentication value */
        ptype = oakley_validate_auth(iph1);
        if (ptype != 0) {
                if (ptype == -1) {
                        /* message printed inner oakley_validate_auth() */
                        goto end;
                }
                evt_phase1(iph1, EVT_PHASE1_AUTH_FAILED, NULL);
                isakmp_info_send_n1(iph1, ptype, NULL);
                goto end;
        }

        /* compute sharing secret of DH */
        if (oakley_dh_compute(iph1->approval->dhgrp, iph1->dhpub,
                                iph1->dhpriv, iph1->dhpub_p, &iph1->dhgxy) < 0)
                goto end;

        /* generate SKEYID to compute hash if signature mode */
        switch (iph1->approval->authmethod) {
        case OAKLEY_ATTR_AUTH_METHOD_RSASIG:
        case OAKLEY_ATTR_AUTH_METHOD_DSSSIG:
#ifdef ENABLE_HYBRID
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_PSKEY_I:
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_RSASIG_I:
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_DSSSIG_I:
        case OAKLEY_ATTR_AUTH_METHOD_HYBRID_RSA_I:
        case OAKLEY_ATTR_AUTH_METHOD_HYBRID_DSS_I:
#endif
                if (oakley_skeyid(iph1) < 0)
                        goto end;
                break;
        default:
                break;
        }

        /* generate SKEYIDs & IV & final cipher key */
        if (oakley_skeyid_dae(iph1) < 0)
                goto end;
        if (oakley_compute_enckey(iph1) < 0)
                goto end;
        if (oakley_newiv(iph1) < 0)
                goto end;

        /* see handler.h about IV synchronization. */
        memcpy(iph1->ivm->iv->v, iph1->ivm->ive->v, iph1->ivm->iv->l);

        /* set encryption flag */
        iph1->flags |= ISAKMP_FLAG_E;

        iph1->status = PHASE1ST_MSG3RECEIVED;

        error = 0;

end:
        if (pbuf)
                vfree(pbuf);

        if (error) {
                VPTRINIT(iph1->dhpub_p);
                VPTRINIT(iph1->cert_p);
                VPTRINIT(iph1->crl_p);
                VPTRINIT(iph1->sig_p);
        }

        return error;
}

/*
 * status update and establish isakmp sa.
 */
/*ARGSUSED*/
int
base_i3send(struct ph1handle *iph1, vchar_t *msg __unused)
{
        int error = -1;

        /* validity check */
        if (iph1->status != PHASE1ST_MSG3RECEIVED) {
                plog(LLV_ERROR, LOCATION, NULL,
                        "status mismatched %d.\n", iph1->status);
                goto end;
        }

        iph1->status = PHASE1ST_ESTABLISHED;

        error = 0;

end:
        return error;
}

/*
 * receive from initiator
 *      psk: HDR, SA, Idii, Ni_b
 *      sig: HDR, SA, Idii, Ni_b
 *      rsa: HDR, SA, [HASH(1),] <IDii_b>Pubkey_r, <Ni_b>Pubkey_r
 *      rev: HDR, SA, [HASH(1),] <Ni_b>Pubkey_r, <IDii_b>Ke_i
 */
int
base_r1recv(struct ph1handle *iph1, vchar_t *msg)
{
        vchar_t *pbuf = NULL;
        struct isakmp_parse_t *pa;
        int error = -1;
        int vid_numeric;

        /* validity check */
        if (iph1->status != PHASE1ST_START) {
                plog(LLV_ERROR, LOCATION, NULL,
                        "status mismatched %d.\n", iph1->status);
                goto end;
        }

        /* validate the type of next payload */
        pbuf = isakmp_parse(msg);
        if (pbuf == NULL)
                goto end;
        pa = (struct isakmp_parse_t *)pbuf->v;

        /* check the position of SA payload */
        if (pa->type != ISAKMP_NPTYPE_SA) {
                plog(LLV_ERROR, LOCATION, iph1->remote,
                        "received invalid next payload type %d, "
                        "expecting %d.\n",
                        pa->type, ISAKMP_NPTYPE_SA);
                goto end;
        }
        if (isakmp_p2ph(&iph1->sa, pa->ptr) < 0)
                goto end;
        pa++;

        for (/*nothing*/;
             pa->type != ISAKMP_NPTYPE_NONE;
             pa++) {

                switch (pa->type) {
                case ISAKMP_NPTYPE_NONCE:
                        if (isakmp_p2ph(&iph1->nonce_p, pa->ptr) < 0)
                                goto end;
                        break;
                case ISAKMP_NPTYPE_ID:
                        if (isakmp_p2ph(&iph1->id_p, pa->ptr) < 0)
                                goto end;
                        break;
                case ISAKMP_NPTYPE_VID:
                        vid_numeric = handle_vendorid(iph1, pa->ptr);
#ifdef ENABLE_FRAG
                        if ((vid_numeric == VENDORID_FRAG) &&
                            (vendorid_frag_cap(pa->ptr) & VENDORID_FRAG_BASE))
                                iph1->frag = 1;
#endif
                        break;
                default:
                        /* don't send information, see ident_r1recv() */
                        plog(LLV_ERROR, LOCATION, iph1->remote,
                                "ignore the packet, "
                                "received unexpecting payload type %d.\n",
                                pa->type);
                        goto end;
                }
        }

        if (iph1->nonce_p == NULL || iph1->id_p == NULL) {
                plog(LLV_ERROR, LOCATION, iph1->remote,
                        "few isakmp message received.\n");
                goto end;
        }

        /* verify identifier */
        if (ipsecdoi_checkid1(iph1) != 0) {
                plog(LLV_ERROR, LOCATION, iph1->remote,
                        "invalid ID payload.\n");
                goto end;
        }

#ifdef ENABLE_NATT
        if (NATT_AVAILABLE(iph1))
                plog(LLV_INFO, LOCATION, iph1->remote,
                     "Selected NAT-T version: %s\n",
                     vid_string_by_id(iph1->natt_options->version));
#endif

        /* check SA payload and set approval SA for use */
        if (ipsecdoi_checkph1proposal(iph1->sa, iph1) < 0) {
                plog(LLV_ERROR, LOCATION, iph1->remote,
                        "failed to get valid proposal.\n");
                /* XXX send information */
                goto end;
        }

        iph1->status = PHASE1ST_MSG1RECEIVED;

        error = 0;

end:
        if (pbuf)
                vfree(pbuf);

        if (error) {
                VPTRINIT(iph1->sa);
                VPTRINIT(iph1->nonce_p);
                VPTRINIT(iph1->id_p);
        }

        return error;
}

/*
 * send to initiator
 *      psk: HDR, SA, Idir, Nr_b
 *      sig: HDR, SA, Idir, Nr_b, [ CR ]
 *      rsa: HDR, SA, <IDir_b>PubKey_i, <Nr_b>PubKey_i
 *      rev: HDR, SA, <Nr_b>PubKey_i, <IDir_b>Ke_r
 */
int
base_r1send(struct ph1handle *iph1, vchar_t *msg)
{
        struct payload_list *plist = NULL;
        int error = -1;
#ifdef ENABLE_NATT
        vchar_t *vid_natt = NULL;
#endif
#ifdef ENABLE_HYBRID    
        vchar_t *vid_xauth = NULL;
        vchar_t *vid_unity = NULL;
#endif  
#ifdef ENABLE_FRAG
        vchar_t *vid_frag = NULL;
#endif
#ifdef ENABLE_DPD
        vchar_t *vid_dpd = NULL;
#endif  

        /* validity check */
        if (iph1->status != PHASE1ST_MSG1RECEIVED) {
                plog(LLV_ERROR, LOCATION, NULL,
                        "status mismatched %d.\n", iph1->status);
                goto end;
        }

        /* set responder's cookie */
        isakmp_newcookie((caddr_t)&iph1->index.r_ck, iph1->remote, iph1->local);

        /* make ID payload into isakmp status */
        if (ipsecdoi_setid1(iph1) < 0)
                goto end;

        /* generate NONCE value */
        iph1->nonce = eay_set_random(iph1->rmconf->nonce_size);
        if (iph1->nonce == NULL)
                goto end;

        /* set SA payload to reply */
        plist = isakmp_plist_append(plist, iph1->sa_ret, ISAKMP_NPTYPE_SA);

        /* create isakmp ID payload */
        plist = isakmp_plist_append(plist, iph1->id, ISAKMP_NPTYPE_ID);

        /* create isakmp NONCE payload */
        plist = isakmp_plist_append(plist, iph1->nonce, ISAKMP_NPTYPE_NONCE);

#ifdef ENABLE_NATT
        /* has the peer announced nat-t? */
        if (NATT_AVAILABLE(iph1))
                vid_natt = set_vendorid(iph1->natt_options->version);
        if (vid_natt)
                plist = isakmp_plist_append(plist, vid_natt, ISAKMP_NPTYPE_VID);
#endif
#ifdef ENABLE_HYBRID
        if (iph1->mode_cfg->flags & ISAKMP_CFG_VENDORID_XAUTH) {
                plog (LLV_INFO, LOCATION, NULL, "Adding xauth VID payload.\n");
                if ((vid_xauth = set_vendorid(VENDORID_XAUTH)) == NULL) {
                        plog(LLV_ERROR, LOCATION, NULL,
                            "Cannot create Xauth vendor ID\n");
                        goto end;
                }
                plist = isakmp_plist_append(plist,
                    vid_xauth, ISAKMP_NPTYPE_VID);
        }

        if (iph1->mode_cfg->flags & ISAKMP_CFG_VENDORID_UNITY) {
                if ((vid_unity = set_vendorid(VENDORID_UNITY)) == NULL) {
                        plog(LLV_ERROR, LOCATION, NULL,
                            "Cannot create Unity vendor ID\n");
                        goto end;
                }
                plist = isakmp_plist_append(plist,
                    vid_unity, ISAKMP_NPTYPE_VID);
        }
#endif
#ifdef ENABLE_DPD
        /* 
         * Only send DPD support if remote announced DPD 
         * and if DPD support is active 
         */
        if (iph1->dpd_support && iph1->rmconf->dpd) {
                if ((vid_dpd = set_vendorid(VENDORID_DPD)) == NULL) {
                        plog(LLV_ERROR, LOCATION, NULL,
                            "DPD vendorID construction failed\n");
                } else {
                        plist = isakmp_plist_append(plist, vid_dpd,
                            ISAKMP_NPTYPE_VID);
                }
        }
#endif
#ifdef ENABLE_FRAG
        if (iph1->rmconf->ike_frag) {
                if ((vid_frag = set_vendorid(VENDORID_FRAG)) == NULL) {
                        plog(LLV_ERROR, LOCATION, NULL,
                            "Frag vendorID construction failed\n");
                } else {
                        vid_frag = isakmp_frag_addcap(vid_frag,
                            VENDORID_FRAG_BASE);
                        plist = isakmp_plist_append(plist,
                            vid_frag, ISAKMP_NPTYPE_VID);
                }
        }
#endif

        iph1->sendbuf = isakmp_plist_set_all (&plist, iph1);

#ifdef HAVE_PRINT_ISAKMP_C
        isakmp_printpacket(iph1->sendbuf, iph1->local, iph1->remote, 0);
#endif

        /* send the packet, add to the schedule to resend */
        if (isakmp_ph1send(iph1) == -1) {
                iph1 = NULL;
                goto end;
        }

        /* the sending message is added to the received-list. */
        if (add_recvdpkt(iph1->remote, iph1->local, iph1->sendbuf, msg) == -1) {
                plog(LLV_ERROR , LOCATION, NULL,
                        "failed to add a response packet to the tree.\n");
                goto end;
        }

        iph1->status = PHASE1ST_MSG1SENT;

        error = 0;

end:
#ifdef ENABLE_NATT
        if (vid_natt)
                vfree(vid_natt);
#endif
#ifdef ENABLE_HYBRID    
        if (vid_xauth != NULL)
                vfree(vid_xauth);
        if (vid_unity != NULL)
                vfree(vid_unity);
#endif    
#ifdef ENABLE_FRAG
        if (vid_frag)
                vfree(vid_frag);
#endif
#ifdef ENABLE_DPD
        if (vid_dpd)
                vfree(vid_dpd);
#endif

        if (iph1 != NULL)
                VPTRINIT(iph1->sa_ret);

        return error;
}

/*
 * receive from initiator
 *      psk: HDR, KE, HASH_I
 *      sig: HDR, KE, [ CR, ] [CERT,] SIG_I
 *      rsa: HDR, KE, HASH_I
 *      rev: HDR, <KE>Ke_i, HASH_I
 */
int
base_r2recv(struct ph1handle *iph1, vchar_t *msg)
{
        vchar_t *pbuf = NULL;
        struct isakmp_parse_t *pa;
        int error = -1, ptype;
#ifdef ENABLE_NATT
        int natd_seq = 0;
#endif

        /* validity check */
        if (iph1->status != PHASE1ST_MSG1SENT) {
                plog(LLV_ERROR, LOCATION, NULL,
                        "status mismatched %d.\n", iph1->status);
                goto end;
        }

        /* validate the type of next payload */
        pbuf = isakmp_parse(msg);
        if (pbuf == NULL)
                goto end;

        iph1->pl_hash = NULL;

        for (pa = (struct isakmp_parse_t *)pbuf->v;
             pa->type != ISAKMP_NPTYPE_NONE;
             pa++) {

                switch (pa->type) {
                case ISAKMP_NPTYPE_KE:
                        if (isakmp_p2ph(&iph1->dhpub_p, pa->ptr) < 0)
                                goto end;
                        break;
                case ISAKMP_NPTYPE_HASH:
                        iph1->pl_hash = (struct isakmp_pl_hash *)pa->ptr;
                        break;
                case ISAKMP_NPTYPE_CERT:
                        if (oakley_savecert(iph1, pa->ptr) < 0)
                                goto end;
                        break;
                case ISAKMP_NPTYPE_SIG:
                        if (isakmp_p2ph(&iph1->sig_p, pa->ptr) < 0)
                                goto end;
                        break;
                case ISAKMP_NPTYPE_VID:
                        handle_vendorid(iph1, pa->ptr);
                        break;

#ifdef ENABLE_NATT
                case ISAKMP_NPTYPE_NATD_DRAFT:
                case ISAKMP_NPTYPE_NATD_RFC:
                        if (pa->type == iph1->natt_options->payload_nat_d)
                        {
                                vchar_t *natd_received = NULL;
                                int natd_verified;
                                
                                if (isakmp_p2ph (&natd_received, pa->ptr) < 0)
                                        goto end;
                                
                                if (natd_seq == 0)
                                        iph1->natt_flags |= NAT_DETECTED;
                                
                                natd_verified = natt_compare_addr_hash (iph1,
                                        natd_received, natd_seq++);
                                
                                plog (LLV_INFO, LOCATION, NULL, "NAT-D payload #%d %s\n",
                                        natd_seq - 1,
                                        natd_verified ? "verified" : "doesn't match");
                                
                                vfree (natd_received);
                                break;
                        }
                        /* passthrough to default... */
#endif
                        /*FALLTHROUGH*/
                default:
                        /* don't send information, see ident_r1recv() */
                        plog(LLV_ERROR, LOCATION, iph1->remote,
                                "ignore the packet, "
                                "received unexpecting payload type %d.\n",
                                pa->type);
                        goto end;
                }
        }

        /* generate DH public value */
        if (oakley_dh_generate(iph1->approval->dhgrp,
                                &iph1->dhpub, &iph1->dhpriv) < 0)
                goto end;

        /* compute sharing secret of DH */
        if (oakley_dh_compute(iph1->approval->dhgrp, iph1->dhpub,
                                iph1->dhpriv, iph1->dhpub_p, &iph1->dhgxy) < 0)
                goto end;

        /* generate SKEYID */
        if (oakley_skeyid(iph1) < 0)
                goto end;

#ifdef ENABLE_NATT
        if (NATT_AVAILABLE(iph1))
                plog (LLV_INFO, LOCATION, NULL, "NAT %s %s%s\n",
                      iph1->natt_flags & NAT_DETECTED ? 
                                "detected:" : "not detected",
                      iph1->natt_flags & NAT_DETECTED_ME ? "ME " : "",
                      iph1->natt_flags & NAT_DETECTED_PEER ? "PEER" : "");
#endif

        /* payload existency check */
        /* validate authentication value */
        ptype = oakley_validate_auth(iph1);
        if (ptype != 0) {
                if (ptype == -1) {
                        /* message printed inner oakley_validate_auth() */
                        goto end;
                }
                evt_phase1(iph1, EVT_PHASE1_AUTH_FAILED, NULL);
                isakmp_info_send_n1(iph1, ptype, NULL);
                goto end;
        }

        iph1->status = PHASE1ST_MSG2RECEIVED;

        error = 0;

end:
        if (pbuf)
                vfree(pbuf);

        if (error) {
                VPTRINIT(iph1->dhpub_p);
                VPTRINIT(iph1->cert_p);
                VPTRINIT(iph1->crl_p);
                VPTRINIT(iph1->sig_p);
        }

        return error;
}

/*
 * send to initiator
 *      psk: HDR, KE, HASH_R
 *      sig: HDR, KE, [CERT,] SIG_R
 *      rsa: HDR, KE, HASH_R
 *      rev: HDR, <KE>_Ke_r, HASH_R
 */
int
base_r2send(struct ph1handle *iph1, vchar_t *msg)
{
        struct payload_list *plist = NULL;
        vchar_t *vid = NULL;
        int need_cert = 0;
        int error = -1;

        /* validity check */
        if (iph1->status != PHASE1ST_MSG2RECEIVED) {
                plog(LLV_ERROR, LOCATION, NULL,
                        "status mismatched %d.\n", iph1->status);
                goto end;
        }

        /* generate HASH to send */
        plog(LLV_DEBUG, LOCATION, NULL, "generate HASH_I\n");
        switch (iph1->approval->authmethod) {
        case OAKLEY_ATTR_AUTH_METHOD_PSKEY:
#ifdef ENABLE_HYBRID
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_PSKEY_R:
#endif
        case OAKLEY_ATTR_AUTH_METHOD_RSAENC:
        case OAKLEY_ATTR_AUTH_METHOD_RSAREV:
#ifdef ENABLE_HYBRID
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_RSAENC_R:
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_RSAREV_R:
#endif
                iph1->hash = oakley_ph1hash_common(iph1, GENERATE);
                break;
        case OAKLEY_ATTR_AUTH_METHOD_DSSSIG:
        case OAKLEY_ATTR_AUTH_METHOD_RSASIG:
#ifdef ENABLE_HYBRID
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_DSSSIG_R:
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_RSASIG_R:
        case OAKLEY_ATTR_AUTH_METHOD_HYBRID_DSS_R:
        case OAKLEY_ATTR_AUTH_METHOD_HYBRID_RSA_R:
#endif
#ifdef HAVE_GSSAPI
        case OAKLEY_ATTR_AUTH_METHOD_GSSAPI_KRB:
#endif
                iph1->hash = oakley_ph1hash_base_r(iph1, GENERATE);
                break;
        default:
                plog(LLV_ERROR, LOCATION, NULL,
                        "invalid authentication method %d\n",
                        iph1->approval->authmethod);
                goto end; 
        }
        if (iph1->hash == NULL)
                goto end;

        switch (iph1->approval->authmethod) {
        case OAKLEY_ATTR_AUTH_METHOD_PSKEY:
#ifdef ENABLE_HYBRID
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_PSKEY_R:
#endif
                vid = set_vendorid(iph1->approval->vendorid);

                /* create isakmp KE payload */
                plist = isakmp_plist_append(plist, 
                    iph1->dhpub, ISAKMP_NPTYPE_KE);

                /* create isakmp HASH payload */
                plist = isakmp_plist_append(plist, 
                    iph1->hash, ISAKMP_NPTYPE_HASH);

                /* append vendor id, if needed */
                if (vid)
                        plist = isakmp_plist_append(plist, 
                            vid, ISAKMP_NPTYPE_VID);
                break;
        case OAKLEY_ATTR_AUTH_METHOD_DSSSIG:
        case OAKLEY_ATTR_AUTH_METHOD_RSASIG:
#ifdef ENABLE_HYBRID
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_DSSSIG_R:
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_RSASIG_R:
        case OAKLEY_ATTR_AUTH_METHOD_HYBRID_DSS_R:
        case OAKLEY_ATTR_AUTH_METHOD_HYBRID_RSA_R:
#endif
                /* XXX if there is CR or not ? */

                if (oakley_getmycert(iph1) < 0)
                        goto end;

                if (oakley_getsign(iph1) < 0)
                        goto end;

                if (iph1->cert && iph1->rmconf->send_cert)
                        need_cert = 1;

                /* create isakmp KE payload */
                plist = isakmp_plist_append(plist, iph1->dhpub,
                                            ISAKMP_NPTYPE_KE);

                /* add CERT payload if there */
                if (need_cert)
                        plist = isakmp_plist_append(plist, iph1->cert,
                                                    ISAKMP_NPTYPE_CERT);

                /* add SIG payload */
                plist = isakmp_plist_append(plist, iph1->sig,
                                            ISAKMP_NPTYPE_SIG);
                break;
#ifdef HAVE_GSSAPI
        case OAKLEY_ATTR_AUTH_METHOD_GSSAPI_KRB:
                /* ... */
                break;
#endif
        case OAKLEY_ATTR_AUTH_METHOD_RSAENC:
        case OAKLEY_ATTR_AUTH_METHOD_RSAREV:
#ifdef ENABLE_HYBRID
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_RSAENC_R:
        case OAKLEY_ATTR_AUTH_METHOD_XAUTH_RSAREV_R:
#endif
                break;
        }

#ifdef ENABLE_NATT
        /* generate NAT-D payloads */
        if (NATT_AVAILABLE(iph1)) {
                vchar_t *natd[2] = { NULL, NULL };

                plog(LLV_INFO, LOCATION, 
                    NULL, "Adding remote and local NAT-D payloads.\n");
                if ((natd[0] = natt_hash_addr(iph1, iph1->remote)) == NULL) {
                        plog(LLV_ERROR, LOCATION, NULL,
                            "NAT-D hashing failed for %s\n", 
                            saddr2str(iph1->remote));
                        goto end;
                }

                if ((natd[1] = natt_hash_addr(iph1, iph1->local)) == NULL) {
                        plog(LLV_ERROR, LOCATION, NULL,
                            "NAT-D hashing failed for %s\n", 
                            saddr2str(iph1->local));
                        goto end;
                }

                plist = isakmp_plist_append(plist, 
                    natd[0], iph1->natt_options->payload_nat_d);
                plist = isakmp_plist_append(plist, 
                    natd[1], iph1->natt_options->payload_nat_d);
        }
#endif

        iph1->sendbuf = isakmp_plist_set_all(&plist, iph1);

#ifdef HAVE_PRINT_ISAKMP_C
        isakmp_printpacket(iph1->sendbuf, iph1->local, iph1->remote, 0);
#endif

        /* send HDR;KE;NONCE to responder */
        if (isakmp_send(iph1, iph1->sendbuf) < 0)
                goto end;

        /* the sending message is added to the received-list. */
        if (add_recvdpkt(iph1->remote, iph1->local, iph1->sendbuf, msg) == -1) {
                plog(LLV_ERROR , LOCATION, NULL,
                        "failed to add a response packet to the tree.\n");
                goto end;
        }

        /* generate SKEYIDs & IV & final cipher key */
        if (oakley_skeyid_dae(iph1) < 0)
                goto end;
        if (oakley_compute_enckey(iph1) < 0)
                goto end;
        if (oakley_newiv(iph1) < 0)
                goto end;

        /* set encryption flag */
        iph1->flags |= ISAKMP_FLAG_E;

        iph1->status = PHASE1ST_ESTABLISHED;

        error = 0;

end:
        if (vid)
                vfree(vid);
        return error;
}